Did you run ANALYZE on your tables before the test? On 4 December 2017 at 16:01, Tomas Vondra <tomas.vondra@xxxxxxxxxxxxxxx> wrote: > > On 12/04/2017 02:19 PM, Nicola Contu wrote: > ...> >> centos 7 : >> >> dbname=# \timing Timing is on. cmdv3=# SELECT id FROM >> client_billing_account WHERE name = 'name'; id ------- ***** (1 row) >> Time: 3.884 ms >> >> centos 6.9 >> >> dbname=# SELECT id FROM client_billing_account WHERE name = 'name'; id >> ------- ***** (1 row) Time: 1.620 ms >> > > We need to see EXPLAIN (ANALYZE,BUFFERS) for the queries. > > Are those VMs or bare metal? What CPUs and RAM are there? Have you > checked that power management is disabled / cpufreq uses the same > policy? That typically affects short CPU-bound queries. > > Other than that, I recommend performing basic system benchmarks (CPU, > memory, ...) and only if those machines perform equally should you look > for issues in PostgreSQL. Chances are the root cause is in hw or OS, in > which case you need to address that first. > > regards > > -- > Tomas Vondra http://www.2ndQuadrant.com > PostgreSQL Development, 24x7 Support, Remote DBA, Training & Services > -- If you can't see the forest for the trees, Cut the trees and you'll see there is no forest.
